Symmetric or Asymmetric the cg is only for static weight purposes and weight hole locations as needed. It has no affect on ball reaction dynamics.
Stack, leverage, negative and countless other old terms are based off a visual of the bowling ball not being thrown. We are smart enough to know that just because the pin/cg or pin /cg/mb are all stacked, that means nothing until someone throws the ball.
If 10 different people throw the same ball with the stacked layout (like a demo days), the actual layout will vary by each person because of the way they throw the ball, where each bowlers pap is will vary. This means the pin to pap, and mb to pap will be different for each. Maybe a little, maybe a lot.
Same ball, same "stacked" appearance, different bowlers. Dual layout, or any other systems is just a better way to find or create desired layout/reactions based off of the more important factors.....the bowler. They all do the same thing by different means.